The present invention relates to the installation of fasteners and, in particular, to a tool for installing collapsible fasteners.
The present invention provides an installation tool for a class of fasteners consisting of axially compressible, radially expandable threaded fastener inserts that are attached to a workpiece and coupled with a threaded bolt to effect a mounting relationship with an associated component. The commercially available inserts, also know as rivet nuts and threaded inserts, are axially compressed by a suitable, thereby radially expanding and securing the fastener for permanent installation on a workpiece.
Inasmuch as substantial force is required to deform the fastener, specialized tools have been developed for facilitating installation. In one approach, as disclosed in U.S. Pat. No. 4,425,782 to Todisco, a hand held setting tool includes a mandrel having a threaded end for holding the fastener and an anvil for axially engaging the fastener against the workpiece. By compressing a pair of pivotal handles, the mandrel is upwardly telescoped relative to the mandrel, whereby the shank of the fastener is shortened causing radial expansion into secure engagement with the workpiece. Thereafter, the mandrel is manually unthreaded from the fastener to complete the installation. The tool requires that the operator use both hands to develop sufficient force to collapse the fastener, presenting safety concerns for installation in difficult to reach locations. Further, the multiple threading steps for mounting and releasing the fastener at the installation tool is cumbersome, time consuming and costly.
To overcome the foregoing limitations of the manual tools, a single purpose, air-powered setting tool, of the type disclosed in U.S. Pat. No. 4,045,994 to De Maio et al., has been proposed for threading the fastener onto the mandrel, collapsing the fastener, and unthreading the mandrel after installation. While somewhat automating the installation procedure and allowing single hand operation, such equipment is very costly, and not affordable to most operators. Further, the tool must be accurately preset to avoid stripping the insert threads during installation.
Accordingly, a need persists for an improved installation tool for collapsible fasteners that is affordable, easy to use, and provides high productivity.
The present invention provides an installation tool for collapsible deformable head fasteners that are automatically operated by widely available and affordable reversible drills. The installation tool includes a yoke assembly supported on the drill housing carrying a reciprocal nosepiece. An actuator shaft is coupled at an inert end to the drill chuck. The other end is provided with a right hand thread for carrying the fastener. An intermediate section of the actuator shaft includes a left hand thread section coupled to the nosepiece. Upon drill actuation, the actuator nosepiece extends relative to the yoke thereby collapsing the fastener into secure engagement with a mounting surface.
Accordingly, it is an object of the present invention to provide an installation tool for deformable insert rivet nuts that may be operated by a readily available power tool.
Another object of the invention is to provide an installation tool for collapsible fasteners that permits single-handed installation.
A further object of the present invention is to provide an installation tool connected to a conventional a reversible drill for safely and quickly installing deformable head fasteners to a workpiece.